Stages of Motor Output Reorganization after Hemispheric Stroke Suggested by Longitudinal Studies of Cortical Physiology
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Open Access
- 29 January 2008
- journal article
- research article
- Published by Oxford University Press (OUP) in Cerebral Cortex
- Vol. 18 (8), 1909-1922
- https://doi.org/10.1093/cercor/bhm218
Abstract
Reorganization of motor circuits in the cerebral cortex is thought to contribute to recovery following stroke. These can be examined with transcranial magnetic stimulation (TMS) using measures of corticospinal tract integrity and intracortical excitability. However, little is known about how these changes develop during the important early period post-stroke and their influence on recovery. We used TMS to obtain multiple measures bilaterally in a group of 10 patients during the early days and weeks and up to 6 months post-stroke, in order to examine correlations with tests of hand function. Ten age-matched healthy subjects were also studied. After stroke, day-to-day variation in performance was unrelated to physiological measures in the first 3 weeks. Measures of corticospinal integrity averaged over the same period correlated well with hand function, but this relationship became weaker at 3 months. In contrast, most intracortical excitability measures did not correlate acutely but did so strongly at 3 months. Thus in the acute stage, patients’ performance is limited by damage to corticospinal output. Improved performance at 3 months may depend on reorganization in alternative cortical networks to maximize the efficiency of remaining corticospinal pathways—intracortical disinhibition may aid recovery by promoting access to these networks.Keywords
This publication has 60 references indexed in Scilit:
- Dynamic Course of Intracortical TMS Paired-Pulse Responses During Recovery of Motor Function After StrokeNeurorehabilitation and Neural Repair, 2007
- Functional potential in chronic stroke patients depends on corticospinal tract integrityBrain, 2006
- Origin of Facilitation of Motor-Evoked Potentials After Paired Magnetic Stimulation: Direct Recording of Epidural Activity in Conscious HumansJournal of Neurophysiology, 2006
- Motor StrokesStroke, 2005
- Interhemispheric Asymmetries of Motor Cortex Excitability in the Postacute Stroke StageStroke, 2003
- Transcranial magnetic stimulation after pure motor strokeClinical Neurophysiology, 2002
- Magnetic transcranial stimulation: dissociation of excitatory and inhibitory mechanisms in acute strokesElectroencephalography and Clinical Neurophysiology/Electromyography and Motor Control, 1997
- Magnetic transcranial stimulation in acute stroke: early excitation threshold and functional prognosisElectroencephalography and Clinical Neurophysiology/Electromyography and Motor Control, 1996
- Transcranial Magnetic Stimulation–Evoked Inhibition of Voluntary Muscle Activity (Silent Period) Is Impaired in Patients With Ischemic Hemispheric LesionStroke, 1995
- The Effect of Destruction of the Corticospinal Tract in the Human Cerebral Peduncle Upon Motor Function and Involuntary MovementsJournal of Neurosurgery, 1968